DB 990 selectamatic ..... restoring underway

[fordguyderrick]

this DB 990 i came across by chance at a local farm when i was a farm contractor .......

i found it abandoned and looking somewhat sad in the corner of a field

thus after coaxing the engine to life ( had to use easy start AAAAAAARRRRRRRRRRRGGGGGGGGGGHHHHH) and paying the farmer scrap price it found its way to my employers yard where after a 4 hour steam clean it looked thus ......

twas at this point i wondered what the hell i had let myself in for

it was more a case of what actually worked than what didnt ... no hydraulics worked, no power steering sytem working ( yes i did liken it to a damn tank and after a rather hair raising road test decided i really should do something about getting some work started on it ), the brakes were somewhat useless and the seat was about ready for the scrap

my ever present father just shook his head and walked away 

[DBfan]

well first of all your nat wise taking that on she will need mudgards and would say that the bonnet is well rotted and as for the hydralics they were some times bad

but.. enogh of that good luck with that and will be watchin this topic closly to see your progress

[powerrabbit]

Strip it back to a bare skid unit, get it all mechanically sound and go from there. If the engine runs well you're 1/2 way there. If you need advice and tips on where to start just email me. All I'll say to start with is drain the engine oil and change it plus the filter, drop the sump pan and clean it all out shiny and remove the oil pump screen basket and clean as well, to get rid of any build-up of sludge which will make the engine breath heavy if there's a lot in the bottom, put on a new sump gasket and re-fill with Universal 15W30. Also clean out the air bath, re-fill to the line same oil as engine and remove and clean out the removable gauze on top the bowl and clean out the 'chimney'. Next change the fuel filters, bleed it through and start it up. Basically a full service. The next stage will be the gearbox oil and filters then you can move on to the hydraulics. Parts are relatively cheap and 99% all available. Well worth restoring.

[fordguyderrick]

thanks tim " you can call me anything you like as long as it's not too late for dinner! "  .....  ( where did you come up with that ? )

im actually a long way through restoring it but i havent taken any new pics since work began

as you said ... the engine oil was cunningly disguised as treacle and the sump was ... well ... lets not go there * shudders *

as for the oil in the engine ... i dont tend to use universal oil in the front end ... i used 15W40 engine oil " for the older diesel engine "

the engine did run when i started work ... but it breathed like a calving cow and smoked like a 1960s factory chimney so its had a full engine rebuild

one thing i did struggle with was getting the timing gears right ... rice krispies had nothing on how it ran the first time i started it after the rebuild 

i had to get a friend who restores tractors for a living to do the timing ..... im not looking forward to doing the implematic at all

[powerrabbit]

Is it the earlier 4/47 engine or the later 4/49? Early one was the same engine as the Implematic 990. You'll probably find that the Imp will be easier to restore but a few parts for these are harder to find new. Have you done the brakes yet? If not, remember to lock down the diff-lock pedal before you remove the right-hand final drive unit! Check that the brake shoe carrier, the round shaft, is screwed in the casting of the axle tight as they can work loose and undo themselves and chew up the brake drum, pays to remove them and put some locktight on the first 3 threads, that's enough to hold them., What have you done to the hydraulics?

Forgot to say, it was my late Father, one of his favourite answers to anyone who asked him what they should call him, Mr. or by his Christian name.

[fordguyderrick]

its the later one ... the 4/49

the tractor itself is a 1970 model

do you know anything about hydraulics on these tractors ... it only lifts when it wants to and its driving me insane

when i emptied the gearbox, the oil was like custard and ive tried everything to get it to work

every time i change the gearbox oil its like custard again within a week and the tractor lives indoors and i have both of the rubber boots over the gear levers

[powerrabbit]

What you need to do Derrick is to drain it all again, a pain I know as it holds around 5 gallons of oil, same as engine oil you need to use. There are two more drain plugs besides the filter bowl plug, a large one under where the cross-bar on the front of the drawbar frame goes across and another under the PTO housing, drain from these as well and you'll get 90% ofthe oil out, these hydraulics like clean oil. If you have lift problems with new oil in then you need to clean the lift valve and bypass valve in the valve chest which is under the dump valve, long knob behind the hidraulic lift quadrant slightly to the right and you have to have the 3-way-valve, handle on the left front of axle, in the right position and also the dial pointer, on the D shaped housing on top the ramshaft right hand casting in the middle. Middle position of this one is 'height', to the right is 'external/TCU' (traction control unit for ploughing) and far left position is 'depth' for ground engaging implements like ploughs, you 'switch' to TCU when ploughing if the ground is soft and you get wheel spin, bit more to it than that but that's the basics. The 3-way-valve is an oil isolator for different 'services' such as trailer tipping from the exactor or operating a front loader. When in the gearbox filter housing make sure you clean out the washable wire gauze screen as well and make sure it pushes up and holds into the paper element which in turn pushes up into the hydraulic oil pickup pipe and being a 'livedrive' don't raise the hydraulic lever until the engine has run for a minute or so or you'll have to bleed the hydraulics to get the air out of the system.

[BC]

Quite a restoration project you have taken on there Derrik but I look forward to seeing more photos of the progress.

[Lord Ferguson]

Thanks for sharing Derrick... Like Billiam above I am looking forward to seeing this project progress.... Starting with a new seat pan for matters of health and safety !

I should also point out that Powerrabbit is a 7 year old school girl from Poland who writes good English but likes to make things up )

[Kiwi6920]

Wow some one else with as much sence as me

i have a 990 imp red and yellow my sump contens would have made you cry, no 1 pistion and liner in the sump...... shes had a internal rebuild runs like a grandfather clock now.....

my biggest problem is the hydros rebuilt the hydo pump, horid thing to get to, and now i have up or down no middle, havent needed it so havent tryed re setting the adjustments yet and i need a tube socket the only size i dont have

good luck and looking forward to update pics

[powerrabbit]

Bit difficult to get at is the hydraulic ajustment, through that little hole on the top left and slightly forward of the PTO housing, there was a 'special' tool for the purpose to turn the nut on the spring. Selectamatic hydraulics are a bit easier to ajust but still fiddely to get at but still relativeley simple to sort out, normal problem with 'no lift' or 'slow lift' is a sticking lift valve or dirt in the bottom of the valve blocking the tiny nylon screen, a gnats whisker will block it.

The Polish girl who speaks good English. 

[fordguyderrick]

7 year old from poland huh ?  ........ * falls off chair in fits of laughter *

i spoke to the farmer i bought it off and he said that the reason it was parked up was he bought a new baler and the mighty white wouldnt power it so it stood outside for the best part of 5 years before i bought it

incedentally ... after all my dad cursed me for buying a " lump of old iron " ...

who was the first to wanna drive it after the engine rebuild ? ...

yup you guessed it ...

this was his idea of a test run in the summer ... hook it up to our international 440B baler and bale 10 acres into small bales

back on topic .....

i will get some new pics of it tomorrow

ive done the gearbox oil change ...

another linkage problem now

THE DAMN THING WONT LOWER .... AAAAARRRRRRGGGGGGGGGGGHHHHHHHH

1st it wont go up ... now i cant get it to go down

any ideas 7 year old girl from poland ?  ...lmao

[powerrabbit]

This little girl from Poland might be bigger than you think!    The lever on the D shaped housing, the dial pointer, should be in the middle position, 'height'. The lever on the left, 3-way-valve, front of axle should be also in the middle position, 'L' which is 'linkage', your lift arms should then lift and lower as they should. If not, look on the left rear of the rear axle and on the back of the rounded casting in which the end of the ramshaft is housed, there should be a curved handle with 'Pull out and lift' stamped on the top of it, this is the hydraulic lift locking device that locks the arms up when you engage it. It should be at 9 O'clock in the lock position and 12 O'clock and come out a little in the unlocked position, when you lift it and lower it you must, with the engine running, raise the hydraulic lever right to the back of the quadrant as far as it will go against the spring and you should hear the pump working which takes the weight off, you can lock and unlock the arms without the engine running, obviously with nothing on the linkage, by lifting the arms with one hand and operate the locking latch with the other. I'm saying this because you may have the arms locked. Dont unlock this way without supporting one lift arm with your free hand otherwise the arms will drop and you could loose a leg bone. If the locking latch is not the problem then you will have to get into the valve chest, that would be another lesson.

[fordguyderrick]

the locking latch is seized solid in the unlocked position and i have found that it operates just fine if something is mounted on the arms ( transport box, haybob etc ) but if theres nothing mounted it refuses to lower no matter where i put the dial pointer and 3way valve ...

which brings me to another point ....

that 3 way lever on this DB actually has 4 positions ... any ideas on that one ?

[powerrabbit]

OK, so the locking latch is in the right position, give it a good spray of WD40 on regular occasions to try and free it but don't try to force the handle as the 2 pins in the casting may shear off. The 3-way-valve, yes, there are four positions but it really only gives you 3 services and the 4th is a double service, far left is for a front loader when the feed pipe to the rams is plumbed into the lower port on the front of the body of the unit, you will see that there are 2 blanked ports. Next position to the right is for the tipping trailer/external exactor service, next right is the double, when a loader is fitted without a separate spool it will feed the oil to both the loader and hydraulic arms and this is used by locking the hydraulic lever right back in the rearmost (Select) position on the quadrant, to lock the lever there should be a pin in the lever shaft below the knob and a latch that hooks over it on the quadrant outer band rear screw stud, this holds the lever in position which gives you constant pump, if there was the decal on the top face of where the handle goes into the 3-way-valve it would be marked L1. The nearest to seat position is the position to operate just the lift arms. You say that the lift arms won't lower without weight, well, they always are very slow without weight, what you have to do is pull up the dump-valve, the tall knob behind the hydraulic quadrant, you should turn it and pull to open it and when not using it, push it down and turn to lock it down. This is connected to the bypass valve and allows the oil to 'escape' through the valve chest quicker, usefull when lowering an empty tipping trailer. Another point about the hydraulics is that on the front of the casting where the handbrake goes through, you will find a knob, this is your 'lowering rate' device, if you turn it one way it slows down the speed that the lift arms lower, designed when using heavy 3-point mounted machinery and implements to let them down slowly and not just dropping 'bang', the more you turn the knob the slower it will lower, basically restricts the rate of oil flow on the return side of the system from the piston. The increase in rate of drop I would say is the opposite and self explanatory. Anything else?

[fordguyderrick]

you have been a great help tim 

just one more thing while im waiting for the new pics of it to upload ...

the steering keeps pulling to the left and i cant figure out why ...

it has the power assisted steering system if that makes any difference

[powerrabbit]

Steering not centralised could be many things. Condition of the ball joints, track setting, wheel hub bearing wear one side, tire size and tread, buckled wheel, bent stub axle and wear in the axle beam pivot (trunnion) pin.  Get the tractor going in a straight line and see how everything I mention is in line or where appropriate, parralel or at right angles. Jack up the axle (front) with both wheels just off the ground and 'wobble' each wheel top and bottom to test bearing movement, rock the steering wheel to see how much play there is in each of the steering  joints and go from there. The power steering unit in itself should not affect the alignment.

[fordguyderrick]

steering sorted ... thanks tim 

as promised ... pics of how she looks now

thus ...

if anyone knows where i can lay my hands on a bonnet ... id be a happy mighty white driver 

[powerrabbit]

Looking good! I think that Ken Jarvis is about the only chap that has bonnet panels, find his ad in 'Classic Tractor' and give him a call. Looking at the seat pan, it's still the original but the bottom has rusted out and a plate put in the bottom. If it's too far gone to repair, replace just the pan with a new one, the black painted pans that they sell for the Fergie 35 is the best but you'll have to cut off the hinge bracket on the back of it. You will se that you can get a complete assembly that includes the mounting bracket for Selectamatic tractors but avoid these as they are far from 'as original' and don't work like the proper one should. Under the seat pan at the rear of the swuare bracket that the pan welds on to, you will see a rectangular cut-out with a 'depression' each end that holds a bar with a rubber roller on it, there should be sort of tab washers that go on each end of the bar of the rollerof which the tabs top and bottom, bend over to hold it all in place. This is for the forward and rearward ajustment of the seat when you lift the square flat 'handle' with the slots in the bottom each side that locate on one of the cross-bars to 'lock' it in place. There's lots of little quirky bits and bobs on David Brown tractors but unfortunateley, those that are re-manufacturing parts for these tractors can only find worn out parts and these little but important bits are often missing so they dont know what should be there and all the new stuff has these missing as well. Just something to look out for and be aware of when buying re-manufacured new parts.

[fordguyderrick]

looking under that seat ... the bottom is actually the plate you see where the bottom of the pan was has rotted out totally

ive found the wiring to ba on the tricky side too ..

i got a new lucas ignition switch and i cant seem to get the wiring to the green charge light on the dashboard to work right anyone got any ideas  ?

[powerrabbit]

The green light on the dash panel is the oil pressure warning lamp which wires into the pressure switch on the engine block on the left-hand side. The red one is the ignition light and if you have a yellow one as well, this is the gearbox oil filter warning lamp, the switch for this is situated under the belly of the tractor just forward of the PTO housing, there is usually a plate covering it for protection. If you can get your hands on an operators handbook for it there's a wealth of information in it which includes a wiring diagram, you find several on eBay and the main Club supply an as original copy of the book, look on their website, www.dbtc.co.uk and click on 'shop', you'll see a lot of other stuff there as well but be warned, they are quite expensive but will give you an idea of what's available. Another good site for parts is www.vapormatic.co.uk I have a trade account with them, my eldest Nephew works for them and their World-wide headquarters is in nearby Exeter, I'm very often in there picking up tractor parts for people.

[fordguyderrick]

this tractor only has a green light and a yellow light  and there isnt a space for a red one

i have a origanal handbook that came with the tractor ... but again this tractor seems different

the wiring diagram has the dynamo / regulator setup ... this tractor has an alternator

[powerrabbit]

Your 990 is the later one with the bored block, AD4/49 engine which is from 1968 to 1972. It has the engine oil filler on the timing gear casing and the assisted power steering unit which was an optional extra. It may be late enough to have been fitted with an alternator from new but still should have the three dash panel warning lamps, red ignition, green oil lamp and the amber hydraulic filter warning lamp, guages fitted were fuel, temperature and the rev/hour counter, should have a push horn button as well. Post up a picture looking straight at the dash panel, I can tell you if it's original then. Your handbook might be for the earlier 990 with the AD4/47 engine, the engine oil filler was on the other side of the engine in the top of the chassis under the lift pump on this model. Look under the dash panel and see if there is a voltage regulator there, an aluminium box, if it's still there it was converted from dynamo to alternator as alternators were'nt fitted as standard until 1972. The serial number stamped on the top of the front casting just behind the radiator just rearward of the bonnet side panel on the right hand side would tell me which year it was manufactured, I can tell you near enough to the month.